CN1299247A

CN1299247A - Planar transducer for measuring biomedical pressures

Info

Publication number: CN1299247A
Application number: CN98814141A
Authority: CN
Inventors: 文森特·凯西; 斯蒂芬·奥沙利文; 罗南·内格尔
Original assignee: Abatis Medical Technologies Ltd
Current assignee: Abatis Medical Technologies Ltd
Priority date: 1998-07-03
Filing date: 1998-07-03
Publication date: 2001-06-13
Also published as: JP2002519679A; US6636760B1; AU8238898A; EP1094747A1; JP4290338B2; WO2000001296A1; DE69828203D1; DE69828203T2; CA2336405C; EP1094747B1; AU758472B2; CA2336405A1

Abstract

A planar pressure transducer in disclosed which is useful for interposing between living tissue and a medical device that applies pressure to the tissue in order to estimate the pressure applied to a selected area of the tissue. The planar pressure transducer comprises a pair of opposed plates between which the proximal ends of optical fibers and a deformable polymer structure and disposed. When the plates are subjected to a pressure acting normally to the plane of the plates an optical signal is obtained via the distal ends of the fibers and related to the pressure acting on the plates.

Description

Be used to measure the flat surface sensor of biomedical pressures

Invention field

The present invention relates to Measuring Object is applied to the pressure on the bodily tissue such as armarium or body part pick off.The present invention be more particularly directed to a kind of novelty and improved pick off, this pick off has by two spaced apart each other pole plates of the flexible member that is formed by rubber at least, and it is used for coming the pressure of measuring vertical in this pole plate effect by the final variation that detects the spacing between pole plate.The present invention is particularly useful aspect health care, this pick off placed on the surface between tissue and the object, and substantially not from this surface moving tissue or object, to measure the pressure that is applied to predetermined position by object.

Background technology

In the application of medical arm-rest belt owing to press the pressure of arteries and veins cuff in the process of medical treatment, to change, so more satisfactory be have a kind of pick off to provide continuously to be applied to following structural actual pressure by this equipment such as cuff.This pick off must have less cross section and relatively the size of cuff want little function or the damaged tissue that does not disturb cuff so that it can be inserted between cuff and tissue.

Usually use " spring balancing principle " and come sensing power and pressure, wherein flexible member is converted to deflection or distortion with measurand in initial sensing step, converts this deflection or distortion to the useful signal of telecommunication in secondary sensing step.Common pressure transducer generally depends on spring, cantilever or diaphragm-operated distortion in initial sensing step, and often answers electricity consumption or light technology in secondary sensing step.

Except the elasticity of polymeric material and rubber, their compliance makes them become the attractive material of selecting of initial sensing step.People such as Miller are in U.S. Pat 3,875, have described the type pad of weighing in 481, and have used elastomer element and developed load cell type pick off, use changes in capacitance and represent institute's applied pressure in this elastomer.People such as Haberl in U.S. Pat 4266263 and people such as Seimiya in U.S. Pat 5,693, the elastomer element of using gap and structure in 886 lag behind and linear response aspect doing improvement.Yet, be difficult to realize best shape without the cutting of complexity and the assembling of assembly program and each equipment.Be also being disclosed in people's such as Boie the U.S. Pat 4,526,043 of designing as touch sensor with the bonded small bore device of elastomer element.Yet, make them be unfavorable for very much usually being applied in the medical applications based on the noise susceptibility of the pick off of capacitor, because require bigger area or require complicated support electronic system that satisfactory signal to noiser ratio is provided.

By the secondary sensing technology of Application Optics can avoid largely with based on the relevant noise problem of capacitive equipment.Disclose such pressure transducer in people's such as Tenerz U.S. Pat 5,195,375, this pressure transducer has the reflector of flexible pressure deformable, and light radiation is reflected from this reflector.This device carries out pressure measxurement on being suitable in medical catheter in situ.Yet they require complicated micro computer process technology with the formation compliant member, and these compliant members are frangible, and are not suitable for the direct mechanical connection.

McEwen is in U.S. Pat 4,869, and in 265 in the disclosed biomedical pressures pick off, but the chamber that includes the gaging pressure of whole diaphragm conversion type electric contact is arranged on tissue and equipment such as between the pressure arteries and veins cuff.When the pressure in this chamber equaled cuff institute applied pressure, opened closed usually contact.The pipeline that application is filled with liquid is delivered to the pressure in this chamber in the checkout gear, and this checkout gear is pressed the arteries and veins point away from this usually, produces the estimator that cuff is applied to the actual pressure of tissue thus.This method does not produce the continuous dynamic estimator of institute's applied pressure, and the influence of the signal attenuation that brings of liquid body pipeline.

Technical scheme

An object of the present invention is to provide a kind of pick off, this pick off can be reliably and is repeatedly measured by any equipment in many armarium and be applied to pressure on some people surface, tissue or the organ.Relevant purpose be this pick off can measure by appointed equipment on respect to this equipment appointed positions and on this preposition perpendicular to the planar direction of this equipment on institute's applied pressure.Further relevant purpose of the present invention is that it can be measured the pressure in 0-500 millimetres of mercury (10psi) scope that applied and it and should be able to measure near this position and generally be no more than 2cm ²Area on this pressure.

Further purpose of the present invention provides a kind of pressure transducer, and this pressure transducer is enough little so that greatly changed in the process of measuring under the situation of tissue/equipment joint face and can not produce bigger error.A kind of relevant purpose is that this pick off can not introduced bigger error when this pick off measurement of application is applied to the pressure that has on the two-dimentional curved surface of radius below 2cm.

Another object of the present invention provides a kind of pressure transducer, and this pressure transducer is suitable for comprising a plurality of sensor arraies.Relevant purpose provides a kind of array of pressure sensors that meets crooked tissue surface.

Further purpose of the present invention provides a kind of pick off that need not use electric current in sensor housing.Relevant purpose provides a kind of pick off that uses metal in sensor housing that do not require.

Further purpose of the present invention provides a kind of permission pick off of calibration or this pick off of verification fast and easily in applied environment.

The present invention has realized above-mentioned purpose.

The flat surface sensor of following measurement biomedical pressures has been realized the present invention, and this pick off is suitable for being inserted in measuring between the limbs of pressing arteries and veins cuff and people or the body part by this pressure arteries and veins cuff and is applied to pressure on these limbs or the body part.This pick off comprises a pair of relative pole plate, and in this pole plate one is a substrate and another is a pressure plare.It also comprises measures passage optical fiber group, and the near-end of this optical fiber group is connected to this pick off, and far-end is connected to electronic module at a distance.This electronic module comprises light source and photoelectric detector and support and processing electronic device.Measure passage optical fiber group and comprise two optical fiber, an emitter optical fiber and the detector optic fibers of measuring the passage light beam from this sensor emission that will measure the passage beam emissions to pick off.Deformable polymer architecture is between pole plate.When exerting pressure for this pick off, the degree that the distortion of deformable polymer architecture projects in the measurement passage light beam light barrier-reflector changes.This has just changed the optical coupling between emitter and detector optic fibers, and the passage light beam is measured in modulation thus.The measuring photodetector that is positioned on the far-end of measuring channel detector optical fiber produces the signal of telecommunication that the intensity modulated of passage light beam is measured in expression.The benchmark passage provides the rheobase calibration signal.Amplify these two kinds of signals and be transferred to analog to digital (A/D) power converter cells.The unitary output of A/D is delivered to processor unit again, and this processor unit is being applied in generation indication on the outut device of pressure.

The accompanying drawing summary

Figure 1 shows that the sketch map of pressure transducer of the present invention and electronic processors circuit.

Fig. 2 (A) is depicted as the pictorial representation of the far-end of measurement and benchmark passage optical fiber.

Fig. 2 (B) is depicted as the viewgraph of cross-section of the optical fiber of the measurement that wraps in the plastic tube and benchmark passage.

Figure 3 shows that the substrate of representing preferred embodiment respectively and the pictorial representation of pressure plare.

Figure 4 shows that the substrate of preferred embodiment and the plan view of pressure plare.

Figure 5 shows that the partial enlarged drawing of the substrate of preferred embodiment.

Figure 6 shows that the diagram of proximal fiber.

Figure 7 shows that the substrate of second preferred embodiment and the pictorial representation of pressure plare.

Figure 8 shows that the substrate of second preferred embodiment and the plan view of pressure plare.

Fig. 9 (A), 9 (B) and 9 (C) represent the end-view and the cross sectional view of preferred embodiment respectively.

Figure 10 (A), 10 (B) and 10 (C) represent the end-view and the cross sectional view of second preferred embodiment respectively.

Pick off diagram after Figure 11 represents to pack.

Figure 12 (A) and 12 (B) represent the cutaway view of the pick off after packing respectively.

Figure 13 represents a plurality of sensor arraies according to the pick off of the present invention's manufacturing.

Implement best mode of the present invention

Shown embodiment wishes exhaustive the present invention or limits the invention in the disclosed concrete form.Selected and described embodiment only is in order to explain principle of the present invention, its application and actual the use, to make other those skilled in the art of this area can utilize the present invention thus.

In preferred embodiment shown in Figure 1, led driver circuit 12 use lower duty cycle and higher electric current and with 1kHz driven for emitting lights diode (LED) 11 so that the signal noise ratio maximum.It is the light energy of 850nm that LED11 produces wavelength.Obviously, some light sources that can also use other except LED produce the light that is used for pick off such as laser diode or electric filament lamp.

Pulsed light beam from LED11 is coupled in the emitter

optical fiber

4,6 of measurement and benchmark passage optical fiber group.Measure passage photoelectric detector 8 and detect the modulated intensity of measuring the passage light beam, and the intensity of benchmark passage photoelectric detector 13 detection reference light beams.

Photoelectric detector

8,13 produces strength signals, and this strength signal is delivered to identical in electronic module 2 but in the signal processing circuit of separating along the holding wire that separates.

Fig. 3,4,5,6,9 have represented the present invention in more detail.In the preferred embodiment that provides, use multistage, multimode fibre.The different fiber of measurement and benchmark passage optical fiber group couples light to LED11 and the

photoelectric detector

8,13 that is included in the electronic module 2 by the gel-filled chemical compound 34 of transparent light.

Specifically, far-end that each optical fiber makes it is set in abutting connection with the light-emitting area of LED11 or the photosensitive surface of photoelectric detector 8,13 (Fig. 2 (A)).Different fiber is included in the cabinet 3, and this cabinet 3 couples together electronic module 2 and pick off 1.This helps to guarantee that all optical fiber has identical path between electronic module 2 and pick off 1, thereby is subjected to similar environmental effect, especially is subjected to the effect of identical bending and microbend power.

Fig. 6 illustrates in greater detail the terminal of the optical fiber group in this pick off.Forming the proximal fiber application epoxy glue 26 of measuring

passage

4,5 longitudinally is connected on the pick off.Then the proximal end face of optical fiber is ground and polishing with concordant and at optical fiber with measure and produce effective optical coupling between the light reflective surface 35 of passage light barrier-reflector structure 24, this measurement passage light barrier-reflector structure 24 is connected to following (Fig. 4) of pressure plare 23 each other.The fiber orientation of using after ultraviolet curing glue 25 will connect is bonded on the substrate 19 (Fig. 6).Benchmark passage

optical fiber

6,7 is assembled according to similar program.

Guide rail 22 is installed on the substrate 19 (Fig. 3), it helps the optical fiber group is set so that the proximal end face of optical fiber is positioned at the distance of being scheduled to apart from the light reflective surface 35 of light barrier-reflector structure 24, as noted before, this light barrier-reflector structure 24 is connected on the pressure plare 23 in measuring passage.Another light barrier-reflector structure 20 with reflecting surface 36 is connected to substrate 19 (Fig. 4) in benchmark passage optical fiber group 6,7.Guide rail 22 also helps to be arranged to make the optical axis of this optical fiber group to be approximately perpendicular to corresponding reflecting surface this optical fiber.

Fig. 3,4,5 have represented substrate 19 and the pressure plare 23 according to the pressure transducer of the preferred embodiments of the present invention, specifically illustrate in greater detail guide rail 22, deformable polymer architecture 21 (Fig. 5) and the light barrier-

reflector structure

20,24 of setting.The substrate 19 of this device is all used identical alumina plate (96%Koyrea) with pressure plare 23.Though use alumina plate in a preferred embodiment of the invention, can widely used interchangeable panel material according to concrete needs.Deformable polymer structure 21 is by forming such as silicone rubber, polyurethane rubber and linear polybutadiene material.Shown in preferred embodiment in, the RTV silicone rubber 9161 that applications catalyst weight accounts for the 2-6% of gross weight forms deformable polymer architecture 21.

In the preferred embodiment of the present invention, RTV silicone rubber also is used for forming track structure 22.These structures also can be used polymer or ceramic dielectric material formation widely.

In the preferred embodiment of the present invention, RTV silicone rubber also is used for forming light barrier-reflector structure 20,24.Hardware with high reflectance can be used as light barrier-reflector structure.Interchangeablely be the metal coating that this structure can also application links to each other with polymer or other non-metallic body.Yet, to use RTV silicone rubber and form the particularly advantageous result of light barrier-reflector and be that it has formed smooth flat surface, this plane surface is the reflector preferably of the wavelength launched in general visible and infrared (IR) emitting diode.In addition, this material can deepening and opaque substantially to visible light and IR radiation.Therefore, can make according to pick off of the present invention with all nonmetallic materials.

Can use many technology comes directly to form polymer architecture on the oxygen aluminium sheet such as lithoprinting, molded and thick film silk screen printing.These technology all have the ability that this polymeric material is formed the various planar geometry with preliminary election thickness.

The structural models of selecting deformable polymer architecture 21 is to produce the best deformation behaviour of this application.Plane mode can be selected from comprise bar shaped, rectangle, circle or criss-cross shape widely.The parameter of the important deformable polymer architecture of controlling comprises the cross section, the interval between each adjacent ledge of each ledge of this structure and in the top of pole plate and ledge and the contact area between the bottom end face.

In the present embodiment, for the ratio (S/W) of the spacing of cross section the best of each ledge and bottom width 0.4 to being to the maximum in 10 the scope (referring to Fig. 5).Greater than 10 o'clock, will produce excessive distortion at this ratio in this structure, this will be increased in the non-linear of relation between the distortion of compressive stress in the housing and housing, reduce the working range of this device thus.On the other hand, less than 0.4 S/W each the adjacent ledge in deformable polymer architecture 21 will be contacted.

Constituting the bottom width of each ledge of deformable polymer architecture 21 and the ratio W/H of height can change between 0.8 to 10.0.8 value will make the ability of this structure opposing shear-type load lower.If the W/H value be higher than 10 the sensitivity of this structure very low so that make that this device is actual can not be as simple pressure transducer.In addition, this also causes lagging behind at institute's applied pressure and in the relation between being out of shape increases.

In order to keep linear response, with the full load limit deformation in 20% of the value of deformable structure height H.This is transformed into A _P/ A _RThe physical constraints of ratio be 8, A here _PBe the gross area of pressure plare, A _RIt is total contact area of deformable polymer architecture 21 and substrate 19.A _RIt is the product of N (quantity of deformable body) and W (bottom width of cross section) and L (length of deformable body).

Select the diameter of optical fiber, the height and the light barrier-reflector 20 of

deformable polymer architecture

21,24 is very important for sensitivity, linearity and the dynamic range of determining pick off, because be (Fig. 3) that measures in the plane at plate apart from d between the light barrier-reflector of special modality and the corresponding optical fiber group proximal end face 39,40.

For the pick off of the preferred embodiment shown in foundation Fig. 5, the ratio of the height H of deformable polymer architecture 21 and fibre diameter D should be in the determined scope of following formula:

1.25 \leq \frac{H}{D} \leq 4

。

If this ratio is greater than 4, then this pick off will be saturated under higher load.Lower limit is represented to guarantee not to be supported on practical limit setting on the optical fiber at higher load condition lower pressure plate 23.

The height of selection measurement passage light barrier-reflector 24 (promptly, slave plate 23 following) so that under the situation of the zero load of pick off, measure the emission of passage optical fiber and detect 10% to 80% the intersecting with the reflecting surface 35 of reflector 24 or overlapping of area of how much ledges of end face 39,40.

Benchmark passage corresponding overlapping is set at roughly 50% usually, though be not strict with accurate value for the operation of the satisfaction of this device.

In a preferred embodiment of the invention, be roughly 0 ° at emitter

optical fiber

4,6 on the near-end 39,40 of each optical fiber group and the angle initialization between the detector optic fibers 5,7.When the spacing d between the proximal end face of the reflecting surface of light barrier-reflector and optical fiber group gives regularly sensitivity maximum by following formula:

d = \frac{D}{2 Tan (Arc \sin NA)},

Here D is a fibre diameter, and NA is the numerical aperture of optical fiber.Better performances for measurement and benchmark passage pick off when this distance is in 1.25 to 1.75d scope.This is corresponding to such zone: the light intensity of reflecting bundle does not highly depend on the accurate interval between optical fiber end and reflecting surface in this zone, and optical coupling produces higher rate of change when measuring in the passage light beam and laterally move to for the reflecting surface 35 of light barrier-reflector simultaneously.

The track 22 that forms on substrate 19 is very beneficial for the initial rough placement of optical fiber.Because optical fiber is provided with, can monitor the initial degree of presetting and adjusting by the output of monitoring

photoelectric detector

8,13 in the process of assembling.

At Fig. 7, second preferred embodiment has been shown in 8 and 10, in second preferred embodiment, use indeformable substantially liner 27 and formed according to pick off of the present invention with deformable polymer architecture 21.The preferable methods of making indeformable substantially liner 27 comprises the RTV silicone rubber 9161 of using the form that is successive basically layer, wherein the thickness of this layer less than this layer width 5% and less than 5% of this layer length.The distortion of liner can be ignored in the pressure limit that this back one condition has been guaranteed to study in the present invention.

This preferred embodiment is especially favourable in the occasion of using the deformable polymer architecture 21 that reduces height.The scope of the practicality of this structure is determined by following condition:

0.25 \leq \frac{H}{D} \leq 1.5

For example, this situation appears below, such as making the height of deformable polymer architecture 21 be similar to fibre diameter or more much smaller than fibre diameter owing to make economic reasons.In this embodiment, indeformable substantially polymer liner 27 is being set directly over each substrate and under deformable polymer architecture 21.Liner is actually a kind of dividing plate, is used for the interval between the pole plate is increased to the optical fiber that is large enough to hold between pole plate, and also allows not to be subjected to this optical fiber to limit, deformable polymer architecture 21 distortion.

The size and the light barrier-reflector 20 of the deformable polymer architecture 21 that is applied in second preferred embodiment and in first preferred embodiment, 24 and at light barrier-

reflector

20,24 and the proximal end face 39 of optical fiber group, the standard of the distance between 40 is identical, and does not describe in further detail at this.

Figure 11,12 have illustrated a kind of mode of packer sensor 1.Packing 28 is made such as HDPE, nylon or polytetrafluoroethylene by a certain nonmetallic materials.The cross section of packing 28 must be little of making whole sensor be in maximum compression.The polymer top cover 29 that is connected to the outer surface of pressure plare 23 guarantees to realize this requirement.In addition, top cover 29 also helps to reduce shearing force to be disturbed, best institute's applied pressure is delivered to pick off 1.

Measure passage optical fiber group and pass the flexible boot 30 that is arranged in the sensor packaging wall.Flexible boot 30 is made by being used in the fibre-optic cable material known usually.The cover inside diameter slightly greater than the optical fiber combination diameter in this optical fiber group in case can easily they be installed in its inside.Then epoxy resin is poured in the cover to be filled in optical fiber and to overlap space between 30 the inwall.This cover provides and has been used for the strain relief pipe that optical fiber passes the flexibility of sensor packaging wall.Structure like can application class in benchmark passage optical fiber group.Molded buffer 31 further protection is provided and can eliminate connection between the optical cable that includes optical fiber group and sensor packaging 28 stress.

It is generally acknowledged that the fiber optic sensor based on the intensity modulated principle is subjected to the influence that following factor causes especially easily: because the influence of source and detector temperature fluctuation, aging effect and along the influence of the variation of the reflectance of the bending of fiber path and environmental effect and reflecting surface.These influences make Strength Changes, and the variation zone that this variation is difficult to cause with intensity modulated by the parameter generating of being studied is separated, and have therefore introduced great uncertainty in measuring process.

According to the present invention, pick off 1 comprises second group of optical fiber, and this second group of optical fiber forms the benchmark passage and be arranged in the cabinet 3 that connects pick off and electronic module 2, and shell 3 also includes measures passage optical fiber.This cover is coaxial with the optical fiber group of combination.Be connected on the substrate 19 with reflecting surface 36 and have proximal end face 40 fixed positions with respect to benchmark passage optical fiber group according to the light barrier-reflector that is provided with as described above.Therefore the luminous reflectance of its predetermined ratio that will launch from fiducial emitter optical fiber 6 is in reference detector optical fiber 7.Therefore reference beam is not subjected to being applied to the modulation of the pressure on the pole plate.Yet, be subjected to the influence of above cited factor easily.Because the optical fiber of benchmark passage is arranged so that between electronic module 2 and pick off 1 to have essentially identical path with measuring passage optical fiber the samely, the intensity that therefore can use the optical signal of benchmark passage is offset the influence of this interference factor to a great extent.In addition ,-DC signal non-by using can be guaranteed the bigger insensitivity to electromagnetic noise interference in electronic processing circuit and electron drift.

In the manufacture process of pick off inherent Several Factors caused uncertainty or inexactness between institute's applied pressure and gaging pressure.How much uncertain, the optical fiber that these factors comprise reflecting surface be connected with optical fiber with respect to the uncertainty of the relative position of reflecting surface and terminal in uncertainty.The same inexactness relevant with measuring-signal can compensate by suitably calibrating each pick off.Specifically, this can realize that these anchor clamps comprise adjustable clamping plate by pick off 1 being placed in the simple anchor clamps, and these clamping plate are pressed on the pressure plare of this pick off so that known pressure is applied on the pick off 1.

In use, pick off 1 can be inserted into and press between arteries and veins cuff 18 and limbs or the tissue (Fig. 1).Design pressure transducer 1 enough thin so that it is not substantially from moving apart tissue with respect to the normal position of pressing arteries and veins cuff 18.The pressure that is applied to this tissue by cuff 18 can application sensors 1 be measured in conjunction with suitable electronic circuit.When pressure was applied to pick off 1, the degree that the distortion of deformable polymer architecture 21 projects in the measurement passage light beam measurement passage light barrier-reflector 24 changed.This variation will change in the optical coupling of measuring between lane transmitter optical fiber 4 and the detector optic fibers 5, and the passage light beam is measured in modulation thus.

Referring to Fig. 1 and Fig. 2 (A), the measuring photodetector 8 that is positioned on the far-end 41 of measuring channel detector optical fiber 5 produces the signal of telecommunication, and this signal of telecommunication represents to measure the modulate intensity of passage light beam.This signal fed back to amplifier 9 before being delivered to processor 16 with digital form, and this amplifier 9 is connected to AD converter 10.

The rheobase calibration signal that obtains from benchmark passage photoelectric detector 13 is to handle with the similar mode of measurement channel signal.Carry out digital processing to produce the reading of output by 16 pairs of these signals of processor then, this output reading is used to compensate the relevant Strength Changes of non-measurement.A kind of straightforward procedure relates to the ratiometer output that obtains expression institute applied pressure.Yet, simple modification compensation technique comprise the using strength reference signal produce feedback control signal in the LED pulse driver circuit 12 with the intensity that remains on the light beam in the benchmark passage on the constant set point level.Two kinds of compensation techniques all are known, do not further describe at this.

Therefore pick off 1 provides the non-electric installation of measuring on a kind of precalculated position under cuff 18 by 18 applied pressures of this cuff to the doctor.

Owing to make the ability of pick off with minimum thickness and width, many pick offs can be connected to flexible shelf layer 32 such as on mylar (trade mark the is Dupont) sheet to form array.Figure 13 has illustrated a kind of 2 * 4 arrays 44, this array 44 is placed on presses the following to produce the measurement that is applied to following limbs or organ upward pressure distribution curve by cuff 18 of arteries and veins cuff 18.Shelf layer provides a kind of connection platform, and this connection platform application stay guy 33 helps fixed plastics shell 3.Layer 32 is also supporting not optical fiber on the same group and is making each optical fiber form fan expediently and launching.

Constitute the measurement passage of given sensor array 44 and four optical fibre packages of benchmark passage optical fiber group and be contained in the flexible polymeric jacket 45, use epoxy glue this cover is connected to shelf layer 32.Must be noted that each pick off 1 is set, to guarantee not violate the minimum bending radius that secular optical fiber that manufacturer recommended bears for making all pick offs feed any bending in this optical fiber by suitable optical fiber group.For convenient, use tacky on two sides band or other simple connecting device whole array 44 is connected on the inner surface of cuff 18.In the control module of each pick off of this array, all have identical drive circuit and signal processing circuit.

Though described current the preferred embodiments of the present invention that we are thought, but those skilled in the art are noted that, do not breaking away from described herein and in the additional claim of institute under the determined prerequisite of the present invention, structure, material, ratio and condition among the described hereinbefore embodiment can change.For example, release the pressure that is applied to pick off though use the modulation of folded light beam in the above described preferred embodiment, very clear, the modulation that can also use the emission light beam.In addition, can use the fiber optic ' T ' bonder and come from the single light source LED of emitter optical fiber to produce the two-beam that is used to measure with the benchmark passage.More particularly, can use fibre bundle beam splitter with demountable adapter for this reason.Similarly, can also use demountable adapter detector optic fibers is connected to photoelectric detector.What it is contemplated that in addition, is this pick off can also be assembled into the very low disposable apparatus of cost with connecting optical fiber and required light source and detector.

Claims

1. flat surface sensor that is used to measure biomedical pressures comprises:

Substrate and relative pressure plare;

Have the measurement passage optical fiber group of near-end and far-end, said near-end connects said substrate, and said far-end connects electronic module at a distance;

Have the benchmark passage optical fiber group of near-end and far-end, said near-end connects said substrate, and said far-end connects electronic module at a distance;

Be arranged on the deformable polymer architecture between substrate and the pressure plare;

Connect the measurement passage light barrier-reflector structure of said pressure plare, said light barrier-reflector has reflecting surface, and this reflecting surface is facing to the near-end of measuring passage optical fiber group;

Connect the benchmark passage light barrier-reflector structure of said substrate, said light barrier-reflector has reflecting surface, and this reflecting surface is facing to the near-end of benchmark passage optical fiber group; And

This sensor arrangement becomes when towards pole plate of another pole plate pressure, measures passage light barrier-reflector structure and changes the light beam that is modulated in the measurement passage corresponding to the distortion at deformable polymer architecture.

2. the described pick off of claim 1, wherein each group of measuring optical fiber group and reference optical fiber group all comprises an emitter optical fiber and a detector optic fibers.

3. the described pick off of claim 1, wherein deformable polymer architecture comprise and can extend to form many ledges of successive line.

4. the described pick off of claim 1, wherein the ratio of the height of the deformable polymer architecture in this flat surface sensor and fibre diameter is between 1.25 and 4.

5. the described pick off of claim 1, wherein measuring passage light barrier-reflector is of a size of: under the zero load condition of pick off, 10% to 80% the area of how much ledges of measuring passage optical fiber group near-end is overlapping with the reflecting surface of measuring passage light barrier-reflector.

6. the described pick off of claim 1, wherein said pick off have the space and extend on the direction perpendicular to pole plate, this space is extended to extend with respect to the space of said pick off in the pole plate plane and greatly reduced.

7. the described pick off of claim 1 further comprises the fiber orientation device with the polymer guide rail that connects substrate.

8. the described pick off of claim 1, further comprise calibrating installation according to the given value calibrating sensors of the pressure relevant with measuring passage, wherein calibrating installation comprises the anchor clamps that are used to clamp this pick off, anchor clamps can move with respect to another anchor clamps, so that predetermined power is applied on the pressure plare.

9. the described pick off of claim 1, wherein said pick off is mounted in a kind of array of this pick off on the flexible layer.

10. the described pick off of claim 9 is wherein selected the size of this pick off and flexible layer, presses between arteries and veins cuff and the limbs so that this array can be inserted in, and with the applying limbs, and cuff surface and limbs surface do not relatively move substantially.

11. the described pick off of claim 1 further comprises:

One group is formed on each pole plate and indeformable substantially liner; Described deformable polymer architecture is arranged between the said indeformable liner.

12. the described pick off of claim 11, wherein said measuring optical fiber group and reference optical fiber group respectively comprise emitter optical fiber and detector optic fibers.

13. comprising, the described pick off of claim 11, wherein deformable polymer architecture can extend to form many ledges of successive line.

14. the described pick off of claim 11, wherein the ratio of the height of deformable polymer structure and fibre diameter is between 0.25 and 1.5.

15. the described pick off of claim 11, wherein indeformable substantially liner comprises successive or semi-continuous polymeric layer.

16. the described pick off of claim 15, wherein the thickness of polymeric layer is less than 5% of this layer width, and less than 5% of this layer length.

17. the described pick off of claim 1, wherein light barrier-the reflector of benchmark passage is of a size of: under the zero load condition of pick off, 10% to 80% the area of how much ledges of benchmark passage optical fiber group near-end and the reflecting surface of benchmark passage light barrier-reflector are overlapping.